Devices or nozzles for intermingling a flow of liquid and a flow of gas are well known. Such mixers may combine a variety of liquids and gasses, but all have the common goal of producing a uniform dispersion of the liquid component throughout the gaseous component.
One particular application in which achieving rapid uniformity of the mixture is especially critical is in the combustor section of a gas turbine engine or the like. In a gas turbine engine combustor, liquid fuel is reacted with air to produce an elevated temperature working fluid which enters a downstream turbine section of the engine. Due to size and weight constraints, the volume of the combustor section of a gas turbine engine is limited in size. As it is necessary that the combustion reaction be substantially completed before the combustion products enter the turbine section, combustor designers have long attempted to increase the rapidity of the mixing of the liquid fuel and air prior to initiation of the combustion reaction.
The accepted method of enhancing the mixing of fuel and air is through increased shear, general turbulence, etc. Shear is generated in the prior art by swirling the air injected with the fuel.
In recent years, awareness of environmental concerns have prompted designers to investigate different methods for reducing the generation of pollutants by gas turbine engines. One pollutant, nitrous oxide, is best controlled by achieving a well mixed, uniform dispersion of the liquid fuel with the combustor air prior to initiation of the combustion reaction. By avoiding pockets or other non-uniform variations of the mixture stoichiometry within the combustor zone, the combustor designer may control the peak combustor temperatures below the levels which might result in the generation of significant nitrous oxide pollutants.